Can I use Valvoline 5w30w synpower oil and how often should I change and can I use 89 octane fuel?
Check your owner's manual on the oil requirement -- Valvoline will be fine but I'm not sure the recommended weight is 5W30. I would change the oil ever 3,000 miles. The fuel is a different issue -- should be a recommended octane level for the car in the manual. Check that and follow their guidelines.
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